import React, { Component } from 'react'
//引入store，用于获取redux中保存状态
import store from '../redux/store'
//引入actionCreator，专门用于创建action对象
import { createIncrementAction, createDecrementAction, createIncrementAsyncAction } from '../redux/count_action'

export default class Count extends Component {

  state = { carName: '奔驰c63' }

  componentDidMount() {
    //检测redux中状态的变化，只要变化，就调用render
    store.subscribe(() => {
      this.setState({})
    })
  }

  //加法
  increment = () => {
    const { value } = this.selectNumber
    store.dispatch(createIncrementAction(value * 1))
  }
  //减法
  decrement = () => {
    const { value } = this.selectNumber
    store.dispatch(createDecrementAction(value * 1))
  }
  //奇数再加
  incrementIfOdd = () => {
    const { value } = this.selectNumber
    const count = store.getState()
    if (count % 2 !== 0) {
      store.dispatch(createIncrementAction(value * 1))
    }
  }
  //异步加
  incrementAsync = () => {
    const { value } = this.selectNumber
    /*
    setTimeout(() => {
      store.dispatch(createIncrementAction(value * 1))
    }, 800) 
    */
    store.dispatch(createIncrementAsyncAction(value * 1, 800))
  }

  render() {
    return (
      <div>
        <h1>异步action版</h1>
        <br />
        <h1>当前求和为：{store.getState()}</h1>
        <select ref={c => this.selectNumber = c}>
          <option value="1">1</option>
          <option value="2">2</option>
          <option value="3">3</option>
        </select>&nbsp;
        <button onClick={this.increment}>+</button>&nbsp;
        <button onClick={this.decrement}>-</button>&nbsp;
        <button onClick={this.incrementIfOdd}>当前求和为奇数再加</button>&nbsp;
        <button onClick={this.incrementAsync}>异步加</button>&nbsp;
      </div>
    )
  }
}
